1. Technical Field
The present disclosure relates generally to surgical instruments, and more specifically to quick connect interfaces used to connect a shaft of a replaceable tool to a drive mechanism.
2. Background Information
Quick connect interfaces (or simply “quick connects”) are widely used in surgical instruments to connect a shaft of a replaceable tool, such as a bit, to a drive mechanism, such as a ratcheting or non-ratcheting handle or a motor-operated drive. These surgical instruments may be used to perform a variety of surgical tasks, including drilling, reaming, tapping, placement of bone screws, assembly of spinal constructs, and the like. One common type of quick connect interface that may be employed is square quick connect interface, often a ¼ inch square (or simply “quarter square”) quick connect interface. Such an interface may be used with a wide variety of different types of replaceable tools, as well as different drive mechanisms.
In a typical ¼ inch square quick connect interface, two ball bearings are generally, positioned radially about a central axis of the quick connect interface, about 180 degrees apart. The shaft may be retained in the interface by operation of these ball bearings, which engage a groove formed in the end of the shaft. The ball bearings are often held by a substantially straight walled portion of the sleeve.
However, while such an arrangement may prevent removal of a replaceable tool, it may not hold the tool very securely. There is often substantial axial and lateral play. There may be minor variations in the shaft of replaceable tools, such that diameters of the groove may vary from one replaceable tool to the next. However, ball bearings positioned radially about 180 degrees apart, and held by straight walled portions, cannot effectively adapt to such variation. This may results in each replaceable tool fitting differently. In some cases, the fit may result in excessive amounts of play, such that the surgical instrument has a generally “sloppy” feel. This feel may be unsettling to a surgeon trying to perform a delicate surgical procedure.
While certain attempts have been made to reduce lateral and axial play, these attempts have often compromised other aspects of the quick connect interface, rendering them impractical. For example, certain attempts have increased the size of the quick connect interface, for example, doubling its size. The increased size may impact the operation and feel of a surgical instrument.
Accordingly, there is a need for an improved quick connect interface.